Pulverized coal burner



Oct. 20, 1931.

G. P. HAYNES PULVERIZED COAL BURNER Filed April 22. 1929 2 Sheets-Sham l Oct. 20, 1931.y

G. P. HAYNEs y PULV'ERIZED GOAL BURNER 2 Sheets-Shen 2 Filed April 22, 1929 Patented Oct. 20, 1931 UNITED STATES PATENT oFFlcE ononon 15. mmm, or BnooxLYN, N Ew Yoan, salomon fro from) DRY nook. EN-

ommmo a narnia ooarona'rron, orimw Yoan, N. Y., A coaronArIoN or NEW YORK rULvEnIzrm com. Brianna Application led April 22, 1929.' Serial No. 356,922.

This invention relates to methods of burning pulverized fuel in a furnace, and my improvements are directed to novel means, in conjunction with a furnace front, having a burner projecting therethrough, wherein a pressure supply of air is communicated to said front for deliveryto the burner in regulated quantities, whereby combustion of the fuel and propagation of the iiame in the furnace are eiclently promoted.

Also my invention comprises the provision of an extended passage-way associated with the diaphragm which constitutesv or forms` part of the furnace` front, for the passage of air, for effecting heat vexchange whereby the temperature of said diaphragm is prevented from becomin excessive, while the air heated in said 'exten ed passageway is available as a medium for drymg the fuel and conveying it to the burner.

Also my invention includes the provision of means, located in the fuel delivery passage-way, for im arting a twist or spiral form to the column o fuel entering the burner, for

the purpose of enabling the combustion supportin air to mix more freely with the fuel in theflunurner.A

Other features and advantages of my invention will hereinafter appear.

In the drawings Figure 1 is a side sectional. elevation of a furnace constructed in accordance with my invention and showing the fuel delivery and air supply means.

Fig. 2 is a front elevation of a two part structure provided with the extended air passageway for heat exchange.

Fig. 3 is a section on the line 3--3 of Fig. 2.

Fig. 4 is a horizontal section on the ine 4-4 of Fig. 2.

Fig. 5 is la detail of the means for connecting the furnace front, diaphragm and burner flange. lin Figure 1 I have shown a portion of a boiler 1 and a furnace composed of a corrugated shell 2, with fire brick lining 3 and an intermediate illingof refractory material 4 that extends out to a front plate or diaphragm 5, said diaphragm forming a boundary for 59 the mouthor entrance to the furnace. The

. parts A-B,v which together have approxifurnace in the exam le shownI is provided with a hollow front that is com osed of the forward late 6 and annular wa 17 that connects wit theshe1l2., p

The burner associated with the furnace, indicated at 8, is of conoidal form, with its larger end opening into the furnace, a radial Hangt? 9 at said larger end co-acting with the diap ragm 5 to close the furnace entrance exteriorly of the burner. l

The'burner has a forward cylindrical neck portion 1 0 that butts against the rearward' end of a curved tubular 'section 1,1 which it self is a continuation of a curved fuel delive tube 12, said tubular section 11 and tube 12 having flanges 11a and 12a whereby they are secured together,-as by bolts 11b.

Located "in or adjacent to the boiler room is a blower 13, a pulverizer 14 adapted tosupply pulverized coal to said blower, and a 7G ho per 15 to feed comminuted coal to said pu verizer, the hopper itself being replenished from a source of supply (not shown), as through an opening 16. As will be. appreciatedby those familiar with the art, pulverized coal is projected by the fan on the pulverizer through tube 12 for delivery to the burner.

lt is intended by me that heated air shall he supplied to the pulverizer as the vehicle for conveyin the pulverized coal from the fan of the pu verizer to the burner, for which purpose I have provided a pipe 17 that extends from vthe furnace front to said pulverizer. 85

As means for providing a source of adequately heated air to serve as the aforesaid vehicle there is shown within the hollow front a two part structure composed of the mately the shape of a horse-shoe, these parts' A-B lying in front of the diaphragm 5 and having a rearwardly directed outside fiange 18 that co-acts with said diaphragm to form an enclosed air space intermediate said twopart structure and diaphragm. Also said parts A-B are provided with an inner boundary flange 19 and with spaced webs 20, 21, which all co-act with the diaphragm to form therewith a return-bend or extended air 100 passage-way, whose course is indicated by the directional arrows in Fig. 2. Said extended passage-way is in communication with the interior of the hollow front by means of an inlet port 22, it being understood that atmospheric air is supplied to said hollow front from the blower by means of a duct 23.

It is to be understood that the duct portion 24,-connecting duct 23 with the hollow furnace front herein illustrated, may also communicate air from the same blower to an- Other furnace or to other furnaces (not shown) in association with the same boiler.

While the inlet port 22 is shown in communication with one end of the extended passage-way hereinbefore referred to, the pipe 17 is shown as connected with said extended passage-way at the other end thereof, so that a column of air traversing said passage-Way, under pressure from said blower, will have its outlet through pipe 17, whence it will pass to the pulverizer for use, as before stated, in conveying pulverized coal tothe burner.

Since the two-part structure A-B is closely associated with diaphragm 5 it follows that air passing through the extended passage-way will serve the two-fold function of lowering the temperature ofY said diaphragm, thereby prolonging its life, while the temperature of the flowing stream of air is raised to a point at which it becomes more serviceable in promoting combustion of and drying the pulverized coal with which it is laden when entering the burner.

The burner 8 is provided with an annularly disposed series of apertures 25, expanded from front to rear in the conoidal example of burner illustrated, for entry of the main supply of air from the hollow front to support combustion of the fuel and air mixture that enters the burner from tube 12 and tube section l1, vanes or dei'lectors 26 projecting inwardly respectively from edges of said apertures to give longitudinal direction to the streams of air entering the burner through said apertures, the spaces between the rearward edges 27 of the vanes and the rearward edges 28 of apertures 25 being closed by members 29 to prevent the direct How of air from apertures 25 into the furnace.

Supported axially within the rearward portion of tube section 11, just in advance of burner 8, is a deflector comprising radially disposed, inclined vanes 30, which have the effect of giving a whirling motion to the column of fuel and air entering the burner.

Said column or mixture of fuel and air thus traversing the burner in whirling form receives the angular impingement thereon of supplies of air entering through apertures 25 and deflected by vanes 26, the thus directed streams of air having the effect of thoroughly carbureting the incoming air and resulting in a highly combustible admixture of the main For the purpose of regulating the quantity of air supplied to the burner through apertures 25 I provide a register in the form of an annulus 31 about the burner, in revoluble relation therewith, said annulus having ports 32 to register with apertures 25, in full open position, and to vary the exposed areas of said apertures in other positions. The annulus 31, which is of conoidal contour to revolubly iit over the burner has a cylindrical neck 33 that encircles the burner portion 10, and it abuts against a thrust bearing collar 34 that provides a joint between portion 10 and the rearward end of tube section 11.

As means for cont-rolling the annulus 3l there is affixed thereto a gear segment 35, in mesh engagement with a pinion 36, carried by a shaft 37, that is journalled in a bearing 38 formed on the tube portion 1l and located within` the hollow front. Said shaft 37 also penetrates a web 39 that extends from tube portion 11 outside the hollow front, and there engages an operating member for its rotation. Said operating member comprises a plate 40, having a handle 41 at one end and a pointer 42 at its other end, the pointer co-acting with a scale (not shown) on web 39 to indicate the adjusted position of the annulus. Also al set screw 43 is extended through plate 40, and adapted to co-act with a plate 40 lying between web 39 and plate 6 of the hollow front, to secure the control means in an adjusted position of the annulus.

An oil burner is indicated at 44 as extended into the tube section 11, with its nozzle projected axially toward the burner, the purpose whereof is to supply oil for initially heating up the furnace, ing the boiler at low pressure or otherwise.

The oil burner is shown as supported by a formation 45 upon the tube section 1l and adjustably secured thereto by a set screw 46. The oil feed pipe is indicated at 47.

Infthe example indicated the outer tube of oil burner 44 is employed as the support for deflector 30.

At 48 there is indicated the usual furnace door.

Variations within the spirit and scope of my invention are equally comprehended by the foregoing disclosure 1. The combination with a furnace having a diaphragm forming the boundary for the and also for operatentrance to the combustion chamber, and a pulverized fuel supply, of means providing an extended passagefway upon said diaphragm, means Ifor introducin la stream ofY air into said passage-way, to e ect exchange of heat with said diaphragm, and means for conducting the heated air from said passageway to the fuel supply.

2. The combination with a furnace having a hollow front, and means for supplying air to the interior of said front, of a diaphragm forming the boundary for the entrance to the combustion chamber, having an extended passage-way formed thereon, coal pulverizing means, a burner projecting through said diaphragm, means of communication between said pulverizing means and said burner,

mea-ns for introducing air from -the interior i of said hollow front into said passage-Way, for heat exchange therewith, and means for conducting the heated air from said passageway to the pulverizer, to serve as the vehicle for drying the pulverized coal and conveying it to the burner.

3. The combination with a furnace having a hollow front, a diaphragm forming ther boundary for the entrance to the combustion chamber, and mea-ns for'supplying air under pressure to the interior of said hollow front, of means providing an extended passage-way upon said diaphragm, means for introducing a current of air from the interior of said hollow front into said passage-way, to effect exchange of heat with said diaphragm, coal pulverizmg means, a burner rojecting through said diaphragm, means or conducting the heated air from said passage-Way to said pulverizing means, and means of communication between said pulverizing means and said burner for the passage tothe burner of the heated air laden with pulverized coal.

Executed this 18th da of A 1.1929. 

